Last updated: February 24, 2025
September weather in Ithaca, United States is characterized by a mix of warmth and precipitation. With maximum temperatures reaching up to 33°C (91°F), the days are undeniably warm, while the average temperature sits comfortably at 17°C (64°F). However, the nights can be brisk, with temperatures dropping to a minimum of 1°C (34°F). This month also sees 91 mm (3.6 in) of rainfall spread over 9 days, contributing to a relatively high humidity level of 78%. As the season transitions, residents experience a vibrant blend of summer warmth and the early whispers of autumn.
In Ithaca, United States, September marks a gentle transition from the sweltering summer months to the crispness of autumn. The temperatures during this month reveal a comfortable range, with minimums around 1°C (34°F) and average highs reaching 33°C (91°F). This fluctuation showcases the lingering warmth of late summer, while the average temperature of 17°C (64°F) provides a pleasant balance for outdoor activities. As the month progresses, the evenings tend to get cooler, hinting at the impending shift to fall. Overall, September offers a delightful respite, beautifully blending the remnants of summer heat with early autumn's embrace.
September in Ithaca sees a modest precipitation average of 91 mm (3.6 in), with rain typically falling over nine days. This marks a slight decrease from the heavier summer months, particularly July, which boasts the highest rainfall at 146 mm (5.8 in). As the seasons transition, September's rainfall tends to create a refreshing backdrop for the early fall, often interspersed with sunny days. The trend of decreasing precipitation from the summer peak suggests a gradual shift towards the drier autumn months, setting the stage for October, which experiences a notable uptick in rainfall to 150 mm (5.9 in), indicating the climate's ebb and flow as the year progresses.
In Ithaca, United States, September marks a transition in humidity levels as summer gradually gives way to fall. With a humidity rate of 78%, September is slightly higher than the summer months of June (79%) and July (78%), indicating a modest increase as the air begins to cool. This trend reflects a larger pattern throughout the year: while winter months often experience soaring humidity levels—peaking at 90% in both January and February—humidity gradually declines during the summer, reaching its lowest point in August at 76%. As autumn sets in, humidity picks up again slightly, hinting at the moisture-rich environment that persists through the later months, leading into the chill of October when levels rise to 84%. Overall, September serves as a bridge between sultry summer days and the crispness of autumn, providing a unique atmospheric blend for residents and visitors alike.
As September arrives in Ithaca, the UV Index begins to show signs of a gradual decline, moving from the peak summer readings. With a UV Index of 8 categorized as very high, residents should remain vigilant, as the burn time is only 15 minutes—similar to the latter months of summer. This slight decrease from August's 9 illustrates a subtle shift towards milder conditions, yet it still warrants protective measures when outdoors. The trend continues into October, where the UV Index drops further to 6, hinting at the approaching autumn. For more detailed insights on daily UV exposure, visit Ithaca UV Index.
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In Ithaca, September marks a vibrant transition as summer fades into fall, bringing 284 hours of sunshine. This month continues the trend of abundant daylight that peaks in the heart of summer, with July and August basking in a generous 341 and 330 hours respectively. As the leaves begin to change, September's sunshine remains plentiful, though it starts to dip from the summer's peak, hinting at the shorter days ahead. The gradual decline in sunshine hours from the 265 hours of May serves as a reminder of nature's cyclical rhythm, reintroducing the crispness of autumn while still allowing for those lingering moments of warmth in the sun.
In Ithaca, New York, September offers a pleasant transition into fall, boasting a 37% chance of sunny weather. This figure showcases a slight uptick from the summer months, which see higher probabilities of sunny days, with June leading the pack at 43%. As the season shifts, the likelihood of sun begins to stabilize compared to the fluctuating chances of earlier months like March and April, where basking in sunlight is far less certain. Overall, while September’s sunny prospects are competitive, they hint at the approaching cooler months, as October's chances drop to 29%. Embracing the autumn allure, September presents a fine opportunity to enjoy pleasant days amidst the changing foliage.
As summer fades into autumn, September in Ithaca heralds a notable shift in daylight, with the sun gracing the skies for 12 hours each day. This marks a gradual decrease from the 14 hours enjoyed in May and June, as the days slowly shorten leading into fall. Interestingly, September still enjoys more daylight than the colder months ahead—November and December each offering a mere 9 hours. This transitional month encapsulates the lingering warmth of summer while hinting at the cozy, shorter days that await, creating a perfect backdrop for outdoor activities as the foliage begins to transform.
As summer transitions to fall in Ithaca, September brings a gentle uptick in wind speed, averaging 3.0 m/s (7 mph). This subtle increase follows a trend of lower winds experienced during the peak summer months, where July and August recorded their lowest speeds of 2.4 m/s (5 mph) and 2.3 m/s (5 mph), respectively. The upcoming months, particularly October with an average of 2.8 m/s (6 mph), show a slight decrease again, reminiscent of the earlier summer months. Overall, September marks a pivotal point in Ithaca’s annual wind cycle, providing a refreshing breeze that hints at the crispness of autumn while reminding locals of the dynamic nature of their seasonal weather patterns.
The weather in Ithaca changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Ithaca and find detailed weather information for every month.
September and January present contrasting weather conditions in terms of temperature and humidity. In September, temperatures can range from a minimum of 1°C (34°F) to a maximum of 33°C (91°F), with an average of 17°C (64°F), creating a warm atmosphere. The month sees 91 mm (3.6 in) of precipitation over 9 days and a humidity level of 78%. Conversely, January is much colder, with temperatures dropping as low as -25°C (-13°F) and peaking at 17°C (63°F), leading to an average of -3°C (26°F). This winter month has a slightly lower precipitation level of 82 mm (3.2 in) but occurs over more days—13 in total—and experiences higher humidity at 90%. For a more detailed look at January weather, you can check Ithaca weather in January.
September and February present strikingly different weather conditions. In September, temperatures range from a minimum of 1°C (34°F) to a warm average of 17°C (64°F), peaking at a high of 33°C (91°F), while attracting relatively moderate precipitation of 91 mm (3.6 in) over about 9 days. In contrast, February experiences much colder temperatures, with a minimum of -23°C (-9°F) and an average of -2°C (28°F), peaking at just 20°C (69°F). Despite the slightly lower total precipitation of 89 mm (3.5 in), it occurs over 14 days, reflecting the persistent winter conditions. The average humidity is higher in February at 90%, compared to 78% in September, emphasizing the damp chill of winter. For more detailed insights, check out Ithaca weather in February.
In comparing the weather patterns of September and March, it is clear that these months present significantly different climates. September typically boasts a much warmer temperature range, with averages around 17°C (64°F) and highs reaching up to 33°C (91°F). In contrast, March experiences much colder conditions, starting with a minimum temperature of -17°C (1°F) and an average of just 1°C (34°F).
Additionally, while September sees approximately 91 mm (3.6 in) of rainfall over 9 days, March has similar precipitation levels at 85 mm (3.4 in), but spread over 13 days, indicating a more persistently damp climate. Humidity levels are also notably higher in March at 87%, compared to September's 78%. For a more detailed look at March weather specifically, you can visit Ithaca weather in March.
In comparing the weather between September and April, we see notable differences in temperature, precipitation, and humidity. September tends to be warmer, with average temperatures reaching 17°C (64°F) and a maximum of 33°C (91°F), while April has a cooler average of 8°C (46°F) and a maximum of 27°C (80°F). However, April experiences more frequent precipitation, with 118 mm (4.6 in) over 16 days compared to September's 91 mm (3.6 in) over 9 days. Additionally, April's humidity is slightly higher at 88% compared to September's 78%. For a more detailed look at April's climate, you can check Ithaca weather in April.
When comparing the weather in September to that in May, notable differences emerge. September typically features a broader temperature range, with minimums around 1°C (34°F) and maximums reaching 33°C (91°F), while May sees lower averages, with minimums around -2°C (28°F) and maximums peaking at 32°C (89°F). Precipitation is slightly lower in September at 91 mm (3.6 in) over 9 days, compared to May's 127 mm (5.0 in) across 17 days. Additionally, September's humidity sits at 78%, while May has a slightly higher average of 82%. For a detailed look at May weather patterns, you can visit Ithaca weather in May.
When comparing the weather in September and June, there are some notable differences. September experiences a wider temperature range, with minimums dipping to 1°C (34°F) and maximums reaching up to 33°C (91°F), making it warmer on hot days compared to June's more consistent temperatures, which range from a minimum of 4°C (39°F) to a maximum of 34°C (93°F). Both months see similar precipitation levels, with September recording 91 mm (3.6 in) over 9 days and June slightly higher at 95 mm (3.7 in) over 12 days. Humidity levels are fairly consistent, with September at 78% and June slightly higher at 79%. For a deeper look into June weather patterns, you can visit Ithaca weather in June.
In comparing the weather of September and July, we see notable differences in temperature and precipitation patterns. September boasts a minimum temperature of 1°C (34°F) and an average of 17°C (64°F), with a maximum reaching 33°C (91°F). In contrast, July has a milder minimum of 10°C (51°F) and a higher average temperature of 22°C (72°F), peaking at 34°C (94°F). Although September experiences less precipitation at 91 mm (3.6 in) over 9 days, it still presents a humid atmosphere with levels around 78%, similar to July, which has a higher total precipitation of 146 mm (5.8 in) across 15 days. For more details on July's weather, you can check Ithaca weather in July.
In comparing the weather of September to that of August, September experiences a broader temperature range, with minimums dipping to 1°C (34°F) and maximums reaching 33°C (91°F), while August maintains a warmer average, with minimums at 7°C (45°F) and maximums peaking at 34°C (93°F). Precipitation is slightly lower in September at 91 mm (3.6 in) over 9 days, compared to August's 100 mm (3.9 in) over 12 days. Additionally, September has a higher humidity level of 78%, compared to 76% in August, contributing to a different overall feel in the atmosphere. For a more detailed look at August weather, check out Ithaca weather in August.
September weather features a wider temperature range, with minimums of 1°C (34°F) and maximums reaching up to 33°C (91°F), resulting in a pleasant average temperature of 17°C (64°F). In contrast, October sees cooler conditions, with a minimum temperature of 0°C (32°F) and a maximum of 28°C (82°F), leading to a lower average of 12°C (53°F). While September experiences less rainfall at 91 mm (3.6 in) over 9 days, October is noticeably wetter, with 150 mm (5.9 in) of precipitation across 15 days, and slightly increased humidity levels of 84%. For more detailed insights, check out Ithaca weather in October.
September and November present strikingly different weather patterns. In September, temperatures range from a mild minimum of 1°C (34°F) to a warm maximum of 33°C (91°F), with an average of 17°C (64°F). The month experiences around 91 mm (3.6 in) of precipitation over 9 days, accompanied by a humidity level of 78%. In contrast, November brings a more frigid climate, with temperatures dipping as low as -20°C (-3°F) and averaging just 4°C (39°F). The month records similar precipitation levels at 95 mm (3.7 in), but is spread over 14 days, resulting in a higher humidity of 89%. For more insights on November weather in Ithaca, check out Ithaca weather in November.
September weather presents a striking contrast to that of December. With temperatures ranging from a minimum of 1°C (34°F) to a maximum of 33°C (91°F), September boasts an average of 17°C (64°F) and significantly lower precipitation days at 9. In comparison, December experiences much colder conditions, with average temperatures hovering around 0°C (32°F) and maximums reaching only 17°C (63°F). The month sees more consistent precipitation over 15 days, with a total of 97 mm (3.8 in), accompanied by higher humidity levels at 86%. For more details about December conditions, you can check out Ithaca weather in December.
As September rolls in, Ithaca experiences a delightful transition from the sweltering summer heat to more temperate conditions. With daytime temperatures averaging a comfortable 17°C (64°F), the month stands out from the warmer days of July and August. Nighttime brings a refreshing coolness, reminding us that autumn is on the horizon. However, don't forget your umbrella—September brings its fair share of precipitation, with nearly a third of the month experiencing rain. The humility of 78% creates a cozy atmosphere, perfect for enjoying the vibrant fall foliage that begins to emerge. For more insights into how September weather compares with other months, check out Ithaca Climate.